26 DRYM^EUS, WEST INDIES. 



bands. This is the typical color-form of the species, historically 

 (figs. 3, 8). 



1 c. The same, but streaks coalescent. 



2. Flesh, salmon or scarlet red, paler above. (Form ludovica 

 'Rang' Pfr., pi. 11, fig. 16). 



2 a. Red or reddish, with three spiral bands, subcontinuous or in- 

 terrupted into spots (figs. 15, 17). 



2 b. Red or reddish, with longitudinal streaks, no bands (fig. 13). 



3. Dirty white, with blue apex and wide spiral zones composed of 

 vertical lines or streaks. (Form apiculatus Gray, pi. 11, figs. 4, 12.) 



4. Fossil in St. Croix ; rather slender with pyramidal spire of flat 

 whorls (form extinctusPh., pi. 11, f. 24-26.) 



5. Small, rather slender, bands when present purplish, " dis- 

 tinguished from all forms of elongatus by the much more lengthened 

 contour, narrow aperture and lip-like internal thickening of the peri- 

 stome" (Form anguillensis Pfr., pi. 11, f. 20-23.) 



None of the patterns of coloring seem to be constant or sharply 

 restricted geographically, although frequently the specimens from 

 one special locality are alike. Thus of 34 specimens from Porto 

 Rico there are 7 uniform white, 5 red, 2 red with bands, 5 whitish 

 with interrupted bands, 10 with narrow streaks, and the rest various 

 transitions. In Tortola the various forms with red ground color pre- 

 dominate, but forms 1, Ib and Ic also occur. Tn a series of 27 from 

 Curacao there are 6 red, 3 red with bands, 2 white, 15 white with 

 bands or spots (some with the apex blue), and 1 white with streaks. 



While I have above given the names applied to various forms, 1 

 do not regard them as of subspecific value ; my conclusions being 

 based upon a series of some hundreds of shells covering every island 

 mentioned in the above paragraph of geographic distribution. 



B. extinctus Pfr. (pi. 11, figs. 24-26), originally described from 

 one specimen, is shown by my series to be absolutely equivalent to 

 elongatus (virgulatus), numerous specimens intergrading perfectly. 

 It is from Pleistocene deposits of St. Croix. 



B. anguillensis Pfr. (pi. 11, figs. 20-23), is typically rather small, 

 slender and pale colored. It also intergrades with virgulatus through 

 the form apiculatus Gray (k'dmmereri Morch). Typical anguillensis 

 is from Anguilla, but a series of twenty shells from St. Croix (pi. 

 11, figs. 18, 19) exactly correspond in form and color, but are thinner, 

 with the lip hardly thickened ; these being the thinnest specimens of 



